What to do with Wood Ashes from the Campfire | Kris Edler

wood ashes in the garden

What to do with Wood Ashes from the Campfire

I recently spent the weekend burning brush from a tree that fell on our permaculture test site at The Daniel Academy.  At the end of the weekend, I realized I had a small problem involving the amount of wood ashes remaining after the fire had long cooled.  In permaculture, one of the keys I learned from my PDC leader, Geoff Lawton, is that “the problem is often the solution.”  So, I asked myself what to do with the wood ashes from the campfire that remained?  How could I give those nutrients back to my environment in a useful way?

img_7678When looking around a permaculture property, there are many uses for wood ash which can be a great source of nutrients for your soil.   However, it’s important to know that with wood ash, your kindergarten teacher was right in saying, “A little dab will do ya.”  Use only a small amount and increase after a few weeks to make sure your soil pH says in the safe zone.  The reason for this is that ashes are extremely alkaline on the pH scale.

Wood Ash is Highly Alkaline

pH for vegetables
best pH for vegetable garden

Because wood ash is a high pH (often 9-13), we have to carefully consider what to do with ashes in our garden.  Optimal soils for most vegetable gardens have a pH of 6.0-7.2, so adding something like wood ashes can have a drastic effect on pH and do so very quickly.  However, using it appropriately can really help nature walk out it’s course of keeping your soil in balance.

Wood ashes are naturally occurring in nature and are a great way for nature to “reset” an environment.  In the Great Plains, the Kiowa Nations would often do controlled burns in order to reset and manage the land.  Next comes California, as devastating as wild fires can be to homes, it’s actually natures way of resetting the damaged landscape and ridding it of invasive annuals that we have brought to the area.  In upstate Washington, the fires clear out understory and add nutrients back to the soil to feed the remaining old growth forests.  This being said, though fire can be a source of destruction, it’s also a source of life in certain circumstances.

Nutrients in Wood Ash

Potassium and potash are two of the prime nutrients are available from wood ash.  The burning process makes them readily available for absorption by your plants.  In fact, potash is so soluble that if it gets wet between the burning process and the time you spread it on your plants, much of the nutrient value will have leeched into the nearby soil.

You can learn more about how to improve your garden soil here:  Ways to Improve Garden Soil

How to Use Ashes in the Garden

There are countless ways to use wood ashes in your garden and around your property, but understanding the soil make-up of your area is the first step before application.  You can easily find out the average pH by purchasing a test kit from a  local garden center.  You can buy kits to test it instantly (lower accuracy) or purchase a kit online that will test it overnight to get a better reading.  Either way, once you know your starting point, you can adjust your pH using organic compounds, like wood ash, to get into the optimal range.  Remember, start by adding only a small amount and give the soil a few weeks to adjust before adding more.  It’s also important to note that various parts of the property could have very different pH readings.

So, now let’s get to it:  How to use wood ashes from the campfire…

1.  Use it in the compost pile

This is especially useful if you are composting a lot of fruit waste, because fruit (being acidic) can really lower the pH of your pile, making it a wet / slimy mess.  You can bring it back into balance by sprinkling a shovel full of ashes over the top.  Always make sure your ashes are completely cool before using.

pH for trees and bushes
pH for trees and bushes

2.  Sprinkle them around berry bushes and fruit trees which prefer alkaline soil or extra potassium.

I generally use them first around apple trees, currants, gooseberries, strawberries, raspberries, blackberries, etc.  They will enjoy the extra sprinkle a few times a year, especially in the early spring or late fall.

3.  Sprinkle on plants to deter pests

This application will only require a small amount of ashes to create a fine dusting.  If you do not have ducks to control snails and slugs, then wood ashes can be a great deterrent.  Carrots and turnips can also be susceptible to the flies and larvae, which can be deterred by the ashes as well.

4.  Light use in the vegetable garden

Often root crops like carrots, turnips, and beets will appreciate a sprinkle of ashes in the springtime worked into the soil.  Just a light dusting is more than enough.  I often use my wood ashes a few weeks before planting and then let it rain a few times before planting seeds.  Other plants that love the extra potash are beans, peas, and legumes.  Just remember, when using ashes in the garden, always test your soil first, so you stay in the optimal zone (6.0-7.2 pH) for growing veggies.

5.  Use them your lawn instead of lime

Wood ashes are a great substitute for adding lime to your lawn.  The easiest way to spread the ashes is to do so just before a good rain, so it soaks into the ground quickly.  This helps with the solubility and also prevents the dust from being tracked indoors or getting on your shoes.  I often use my grass seed spreader and put it on the lowest setting and broadcast the ashes that way.  Doing it by hand or with a shovel can often create piles in the grass which will over alkalize an area.

Now that you have a good use for those ashes, go outside, make a campfire and have a s’more (or three) and let us know how you have used the ashes when you are finished.  Again, make sure they are cool before spreading.  Remember, the problem is often the solution.  Happy gardening.